Gibson's "Mastertone" line of higher-end
banjos debuted in 1925 with style
5 as its highest-priced model.
Style 5's specifications included
a walnut neck and resonator with two
concentric rings of multicolored wood purfling on the back of the resonator:

The neck, resonator,
and bottom of the rim were bound with this same multicolored purfling along
with, in most cases, what Gibson called "iridescent ivoroid":

Style 5
banjos also featured an oval and fan design in wood marquetry on the back of the
peghead:

The
hardware was gold-plated with engraving on the tension hoop, armrest, tone ring
skirt, flange, and tailpiece. The earliest style 5 Mastertones had
grooved tension hoops with flat hooks, first seen in conjunction with holes in
the outer tone-ring skirt:

This first Mastertone
tone ring was the ball-bearing design with sixty holes; later examples had no
holes in the outer skirt:

Throughout the production run of the style 5
Mastertone, the peghead was fiddle-shaped and, along with the rosewood
fingerboard, was inlaid with the "wreath" pattern in mother-of-pearl:

The
earliest version, seen primarily on examples from 1925, had the word "Mastertone"
inlaid in small individual letters on the peghead just under the script "Gibson"
logo:

Circa 1926, the word "Mastertone"
moved to a mother-of-pearl block at the end of the fingerboard:

Circa 1927, all
Mastertone models including style 5 changed from the ball-bearing tone ring to a
cast metal raised-head, or archtop, tone ring. While the exterior
"beveled" appearance of the head remained the same, the new tone ring
construction is evident inside the body. Some of the earlier raised-head
rings had no holes. . .

. . . while the
forty-hole variety soon became the standard on all Mastertone models:

With the change to cast
raised-head tone rings also came a change to notched, rather than grooved,
tension hoops with round, rather than flat, hooks:

Style 5
Mastertones of the 1920s were typically equipped with Kerschner tailpieces
engraved with the word "DeLuxe". . .

. . . while a few later examples were equipped with the Grover "clamshell"
tailpiece:

Style 5 was discontinued with
the introduction of style 6
in 1928 and remained out of production until being revived briefly by Gibson as
a reissue model in the 1990s.